The human body has an organ called the thyroid gland, and the thyroid gland is mainly responsible for the secretion of thyroxine. The main roles of thyroxine are as follows: 1. promote the metabolism of substances and energy, and promote the process of growth and development of the body; 2. have a thermogenic effect, which can increase the basal metabolic rate, promote the absorption of sugar by the small intestinal mucosa, enhance glycogen decomposition and inhibit glycogen synthesis; 3. strengthen the glucose-raising effects of adrenaline, glucagon, cortisol and Growth hormone glucagon; 4, strengthen the use of sugar in peripheral tissues, lower blood sugar, but also promote fatty acid oxidation, enhance the catecholamine decomposition of fat, but also promote the degradation or synthesis of cholesterol.